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Three habitable worlds found around the same star

ALIENS could be watching aliens watching aliens. That’s a realistic prospect now that three potentially habitable planets – a record – have been glimpsed orbiting the same star.

Earlier studies had suggested that a nearby star, Gliese 667C, had three planets, only one of which might support life. But the very presence of multiple planets made their precise number hard to tease out.

Now Guillem Anglada-Escudé of the University of Göttingen in Germany and his colleagues have reanalysed the original data and added some new observations. They found evidence for up to seven worlds, including three rocky planets where temperatures should suit life (Astronomy & Astrophysics, in press). The three are close enough to each other that any intelligent life there with the ability to build rockets could visit the neighbours in just one to two months.

In 2010, two of the paper’s authors were praised and then criticised when they claimed to have found the first potentially habitable rocky planet around the star Gliese 581 – a discovery others were unable to confirm. Anglada-Escudé is not worried&colon; “We made sure to be very careful this time.”

This article appeared in print under the headline “Trio of alien planets”